Thermoelectric system for remote object images



Sept. 23, 1952 R. H. RINES 2,611,394

THERMOELECTRIC SYSTEM FOR REMOTE OBJECT IMAGES Filed July 18, 1945 ,qrronwev.

Patented Sept. 23, 1 952 UNITED STATES PATENT OFFICE THERMOELECTRIC SYSTEM FORREMOTE OBJECT IMAGES Robert Harvey Rines, Brookline, Mass. Application July 18, 1945, Serial No. 605,721

. 24 Claims.

The present invention relates to electric systems, and more particularly to radio-receiving systems that, While having-more general fields of usefulness, are-especially adapted for use in television. a I

An obect of the invention is to provide a ne and improved radio-receiving system. a I

Another object is -to provide a new and improved television system. I Another object is to provide a novel combined radio-and-television system. i (Y 'Another object of the present invention is to provide a new and improved radio-locator system for bothdetecting the presence of a body and rendering it visible.

Other and further objects will be explained hereinafter andwill be more particularlypointed out in the appended claims. l The invention will now be more fully explained in connection with the accompanying drawings, in which Fig. 1 is a diagrammatic view of cirwits and apparatus arranged and constructed in accordance with a preferred embodiment thereof, showing also the airplane object from which the radio waves are reflected and scattered to the receivingsystem; Fig. 2 is asection of a modification, upon a smaller scale, taken upon the line.2-2 of Fig. 1, looking in the direction of the arrows; and Fig. 3is a view of a common thermocouple analogous to the .iorm shown in Figs. 1 and 2..

An electromagnetic-wave generator 4 is shown exciting a dipole .2 to produce ultra-high-frequency. microwave radioenergy, say, of 3 or 1.5 centimeters wave-lengths A. continuous-wave or any. other type of modulated-wave generatormay be employed, though pulsed energy, at present, has the advantage of economical and easy highpower ultra-high-frequency generation.

The waves. emitted by the dipole 2 may be directed by a reflector 3 upon a parabolic reflector 6. The. parabolic reflector 6 is shown directing the waves toward an object, say, an airplane 9, from which they are reflected and scattered toward a receiving station.

At the receiving station, the radio waves .thus reflected and scattered from the object 9 may be focused by an electromagnetic dielectric lens 5, such as polystyrene, upon a bank or array 1, comprising a plurality of normally-ineffective insulated radio-receiving pick-up unit antenna elements. The dielectric lens may be replaced by any other type of well-known lens, mirror or other directive systemfor focusing the electromagnetic energyscattered and reflected from the object 9 on the bank or array '1 of antenna elements.

The pick-up elements may be in the form of thermoelectric devices operating accordingto the Seebeck efiect. Two such elements are -illus-"- trated in Fig; 3, constituted of two dissimilar metal elements It and II of, say; Eureka and copper or steel. They are joined togethe'rby any well-known thermocouple solder'connectingelement 8. The --elements In and H are shown respectively provided with dipole" segments-3|! and 1..

These dipoles will receive a transmitted electromagnetic wave, whereupon heat will-be pro duced with differential effects in theelemnts Ill and I l, resulting in an unidirectionalthermo electric electromotive force in electrodeterminals 40 and H of the respective"thermocouple elements in and II. The radio-frequncywill be short-circuited in the dipoles wand 31 but a direct current will be caused to travel= in the conductor extensions 40 and 4|. Radio frequency energy on the left-hand side of thej'unctionll,

therefore, is converted into direct current in the terminals 40 and M on the other sideLAmechanism is thus provided for rectifyingthe radio frequency energy. As described in theAdmiralty Handbook of Wireless Telegraphy, 1938, section W, paragraph 6, the electromotive force isrp'roiportional to the temperature and' the heating to the square'of the radio-frequency current.

The thermoelectric antenna. elements are .shown arranged in the form ofrows andcolumns,

example, is illustrated as comprising the.thermocouples l0--l I, l2--l3, 14-45, I6-..-l8,tetc.:,shown as equally spaced horizontally. I The length of the segments Ill-4 I, etc., up to the junctions .8, may bea quarter-wave lengtheacht. .The' second row from the top is. shown comprising the sections 22.-24,.28-29, etc. Thoughronlyla small number of antenna units is shownineach row, this is merely for illustrative purposes, in--order not to confuse the disclosure. It will be understoodthat, in practice, a large number of antenna units will be employed in each row. order to fix the ideas, for purposes of description, let'that number be chosen as180. f I P The columns and rows are separated by t e insulation strips l. Though each"-column is shownas comprising only a few antenna units, this is again in order. not to complicate the crew'- ings. In actual practice, the number of antenna strips in each column maybe quite largeg sayllwl 3 The direct-current sides of the thermocouples are shown disposed in a long illuminating cell such as a neon or other gas cell, directly behind the pick-up elements of the corresponding row,'

and'may contain a suitable gas, such asneon,

to constitute a gas cell. A screen 50, disposed at the rear faces of the cells, maybe constituted of darkened transparent material to serve as a suitable weak filter. If neon is the'gas employed, the filter preferably should be orange-colored.

Electrodes are shown mounted at the ends of the-cells to provide initialstriking .voltages for the gas cells. An initial glow may be produced in ,thetopcell 23 by impressing a low; directcurrent, potential upon the electrode 20, com

, pared tothat'ofthe electrode I9.

.An:initialglow may, similarly be-produced in the second cell .33 by impressing: a lowdirectcurrentpotential upon the electrode 26, ascom- .paredwiththepotential impressed upon the electrodes; and so on foraother, correspondinglypositioned electrodes; The pairs ofelectrodes are shown connected in parallelyacross a battery 21. for, permanently-impressing these directrcurrent striking potentials. A. glow dischargea will" thus be established through the .variouszgas discharge neon cellsbetweenithe said electrodes.

..., The .thermoelectric -antenna-section units will, of course, allreceiveltheyreflected or scattered radio waves through the lens .5 simultaneously. Therei will'be focused on each antenna. section aradio-frequency voltage, corresponding to the scatteringfrom'a ccrrespondingjarea of the ob- .ject 9.

@Thevpick-up elements will thus .receive. dif- Ierent'field; strengths of reflected or scattered radios-energy, -.corresponding to. the amount of ener y reflected or scatteredzfrom-the zvarious partsg'ot'the objects; and convergedupon: the array.of.pick+up:,.elements:'by the lens- 5.. A radio-energy picture. of, the .object 9 is thus recorded}: upon :the; array, specific elemental areas .of.-' :which. will 1 correspond to specific elemental areasof the object 9, and-this specificeelementalareaxcorrespondence. willbe preserved by. reason of-mthefact thatrthere is no discharge between the: ithermo electric-couple antenna elements.

. Byr'means of.-.the.*present invention; thisfradioenergy picture may beconverted into a faithful visibleipicture.v The. present invention, however, isgto be contrasted with prior-art-proposalszfor converting radio energy into a visual indication by; causing radio-receiving .elements to produce radio-frequency discharges, between one another, thereby: 1 destroying, such .specific-elementalearea eorrespondenceand distortin'gaany possiblevisibleg-likeness.

The received radio energy, by the Seebeck effeet, will produce corresponding direct-current ,voltages continuously to disturbor modify: the normal relation. between, the electrodes l9-2U, 2 5-I-.-,- Z6,; etc.,. of the .gascells inwhichthey. are disposed. .Thejflglow through the various portions of the neon cells will become-correspondw inglymrnodified "in: accordance--withithe:directcurrent voltage produced from the radio-frequency energy received by the corresponding antenna elements.

By suitable design, it is possible to operate on a portion of the characteristic of the neon cell such that a nearly linear relationship shall exist between the direct-current excitation and the illumination or glow intensity of the neon cells, within the range of operation. ;The radio distribution received by each thermo-couple radio-receiving element may therefore be con- .verted, according to the present invention, into a corresponding light distribution. 7 V H 1 1T0 fix the ideas, consider'the' cell 23, for example, where a direct-current potential is estab- '..lished by. the battery 21 between the electrodes l9 and 20.

This causes ionization of the neon and a'slight orange glow between the electrodes l9 and 20. The impressing oi radio-frequency energy on the dipole HJH, converted into direct-current voltage by the thermocouple thereof, willv cause. the part ofsthe neon cell assooiatedwith the conductor extension-electrodes 40 and 4| on the other side ofthe thermocouple l0ll to glow with an additional modifying orange glow the-intensity of which bears afixed relation to the amount of radio-frequency energy.

Unlike the before-mentioned prior.-art -;systems, there will be little orno interference between the glows in the cells .-behind-,adjacent antenna sections, because 1 the gas-glow; or 1- discharge boundaries between the direct-current side of the antenna sections, such as those-between the electrodes 40 and 4 I are rathersharply defined, and only direct-current voltages 2 2.18 present in the gas. The discharges-are atgiright angles to the background-discharge in: the cells, as between the electrodes l9 andv 20 The slightly darkened aspect produced by the orangecolored filter 5c will help. to ,keep the daylight ofi the gas, thus preventing afiecting'theignition characteristics. The-weak orange filtering-:action serves also to help produce the additional orange glow in respose togthe radio-frequency signals, filtering out the background of the orange directcurrent glow, and thus helping to produceong-the bank of neon cells the visible image of the object' 9, as impressedfin' radio-frequency form, on the antenna sections.

Separate neon tubes may, .howeverybevem ployed, with separate cathodes, connected to the respective radio-receiving elements. A'uniforrn background may'zcbe; attained in-"this manner. The picture of the object 9 would be'visibleon the neon cells themselves, ifvsuch separate-bells were employed. Instead ofthe direct-current ignition potential from the battery 21, m'oreover, a striking radio-frequency voltage,- suitably 'attenuated, may be applied to the cells from the transmitter 4. i The neon cells :may, furthermore; be supplied with control-grid electrodes and: anodes, omitted from the drawings,- for' the sake of simplicity. If the radio-frequency-signals should be weak, theymay be enhance'd by means of amplifiers-between theantennas and the-neon cells. A radio-frequency shield51 0f any suitable material, such as mesh 'wire, may be'interpo'sed between the cells and the pick-up elements l0l'l, 'etc.,' to lessen the'likelihood of interference effects of-the-radio energy andathe electrodes and elements in the cells. A"likenesscorresponding; to-the radio energy received by the radio-receivingp'array I ofantennaewill thus be electromagnetically produced on the screen of; the gasrdischar e:..ineon :cells;

This likeness will be a distinct, definite sharp visible image of. the distant object. The definition of the likeness depends merely upon the size of the thermoelectric elements and their number- The greater the'number of the elements, and the smaller their size, the more sharp will be the definition. 180 rows and columns of antenna sections or] dipole dimensions will yield good definition for large close-range objects, particularly for a three-centimeter wave, assuming an eight-foot screen 50.

Althoughthe invention has been described in connection with antennae arranged in rowsand columns, it will be understood that this is not essential, for other arrangements are also possible. Antennae arranged along concentric circles covering the field, or a continuous spiral, will also serve. l r Further modifications will occur to persons skilled in the art, and all such are considered to fall within'the spirit and scope of the invention, as defined in the appended claims.

What is claimed is:

1. An electric system having, in combination, means for receiving radio waves, gas-discharge means, and thermoelectric-couple means controlled in accordance with the thermoelectric operation of the thermoelectric-couple means for producing on the gas-discharge means directcurrent glow discharges defining a likeness corresponding to the energy distribution received by the radio-receiving means.

2. An electric system having, in combination, a plurality of thermoelectric-couple radio-wave receiving elements, gas-discharge means having portions each corresponding to one of the elements, and means controlled in accordance with the thermoelectric operation of the radio-wave receiving elements for energizing the said portions of the gas-discharge means in accordance with the thermoelectricity in each of the elements resulting from energy received by each of the elements to produce a likeness corresponding to the energy received by each of the elements.

3. An electric system having, in combination, thermoelectric-couple means for receiving radio waves from an object, gas-discharge means, and means operable in accordance with the thermoelectric operation of the thermoelectric means and responsiveto the thermoelectricity in the thermoelectric-couple means and controlled by the received radio waves for producing on the gas-discharge means a likeness of the object.

4. An electric system having, in combination, a plurality of thermoelectric-couple radio-wave receiving elements, gas-discharge means having portions each corresponding to one of the elements, means for striking glow through the gasdischarge means, and means for modifying the glow of the-said portions of the gas-discharge means in accordance with the thermoelectricity ineach of the elements resulting from the radiofrequency energy received by each of the elements.

5; An electric system having, in combination, a plurality of radio-wave receiving elements, electrode means, means for producing a glow discharge between the electrode means, and means for modifying the glow discharge between the electrode means with direct-current glow discharges in accordance with the energy received by each of the elements.

6. An electric system having, in combination, a plurality of thermoelectric couples for receiving radio waves from .anobject, each thermoelectric couple corresponding to .an, elemental portion of the object from which it receives the radio waves, and gas-discharge means responsive to the thermoelectricity produced in each oil-the thermoelectric couples by the radio waves from the corresponding elemental portions of theobject for producing elemental portions of a likeness of the object corresponding to 'theJ-ra'dio waves received by each of the correspondi thermoelectric couples. 1 :5

'7. An electric system having, in combination, a thermoelectric couple comprising twoelements of dissimilar metals for receiving radio waves and an electrode connected to each of therele ments, the elements having dimensions resonant to the radio waves, and gas-dischargemeans responsive to the energy produced in the electrodes by the received radio waves for producing a visual indication of the received radio waves.

8. An electric systemhaving, in combination, a plurality of radio-wave receiving-and-rectiiying elements for receiving and rectifying radio waves from an object, gas-discharge means, and means connecting the elements and the gasdischarge means for producing rectified directcurrent discharges in the gas-dischargemeans. thereby to produce a likeness of the object i 9. An electric system having, in combination; a plurality of thermoelectric-couple elements -=for receiving and rectifying radio waves from an object, gas-discharge means, and means con necting the elements and the gas-discharge means for producing rectified direct-current discharges in the gas-discharge means, thereby to produce a likeness of the object. I I

10. An electric system having, in combination, a plurality of thermoelectric-couple elements for receiving and rectifying radio waves from an object, each thermoelectric-couple element corresponding to an elemental portion of the'object from'which it receives the radio waves, andgasdischarge means responsive to the rectified energy produced in the thermoelectric-couple elements by the radio waves from the corresponding elemental portions of the object for producing elemental portions of a likeness of the object corresponding to the radio waves received and rectified by the corresponding elements.

11. An electric system having, in combination, a plurality of radio-wave receiving elementsfor receiving radio waves, gas-discharge meanshavsing two electrodes, means for striking a firstgastricity in the thermoelectric couple means for' producing a likeness of-the object.

13. An electric system having, in combination,-

a plurality of first bimetal thermocouples resonant to radio waves for receiving radiowaves from an object, a plurality of second bimetal thermocouples, one corresponding to*eacli' of the first thermocouples, means for impressing iipcn'lzieachezsecondze thermocouplesthemn tage Cth'ermoelectricity produced:i-rr'thelsecondzthermoe couples'iina response:torthetradio.waves-deceived bycthesfirst thermocouplesiifors pro:ducingva:llikene'sszsrof Ethel :ohject lcorrespondingl .-toi the:2aadi0 energy recelve'dztby thezrfirstathelimocouples? from th'ezobject V 4st zAmelectric system having, in combination, thermoelectric-couple means "JfOI'J: recei-vi'ng xradio waves;- lgasedischarge lmeansy-l-means; for producingeracibackgroundr gas discharge through: the .gasedischargea means; means controlledi bye the received i radiowaves: for mod-ifying-z the: :background :ofuzthe, gas :discharge -and: means for iiiterings out; the; lunmodified-background gas discharge. l-5n nnlelectric system having, in:combination, thermoelectric-couple? means for receivingradio walrles;=-*gasedischarge means, means .for striking a'isuflicient background:- gas" discharge through theses-dischargemeans-to operate the gas-discharge. grneans-in accordance with a characteristic curve provided, -with-a substantially linear portion along which the intensity of illumination of the gas varies substantially linearly with the intensity-rot excitations-energy, and means controlled-by the received radiowavesand operative on: therlinear portion of the characteristic curve-for modifying the-background gas-discharge. l l6,-; An; electric-system having, in combination, aatwo-dimensional array of, gas-discharge, elements. and thermoelectric couple radio-receiving means for receiving radio wavesfroman objectyand connected to and cooperative with the gas-discharge elements to produce a likeness of the object. I a

17. :An electric system having in combination, a. plurality ofthermoelectric-couple radio-wave receiving elementsfor simultaneously receiving radio waves-from an object, illuminatingrneans, and .means for permanently electrically connecting-the-radio-wave receiving elements to" the illuminatingmeans continuously to control the illumination 'of the illuminating means in accordancewith the thermoelectricity produced by the received radio waves in the radio-wave receiving-elements; inorder to produce a likeness 'cfthe object upon-the illuminating means simultaneously with the reception ofthe radio-waves by the radio-wave receiving elements.

:18. Anelectric system having, in combination, a plurality of radio-wave receiving-and-rectif yiingielementsfor receiving and rectifying-radio- :wave energy from an object,-illuminating-means, and means for permanently electrically connecting the radio-wave receiving-and-rectifying elements to the illuminating means continuously to control atheillumination vofthe illuminating means inv accordance with the: rectified energy .produced by the radio wavesin the radio-wave receivingr-and rectifying elements in order to .producea likeness of the object upon theiilluminating meanssimultaneously with thereception of, the radio waves by the radio-wavereceivingand-rectifying elements.

19. An electric system having,incombination, radio wave. receiving 7 means for receiving radio waves from an object comprising antenna means provided with electrical conductors and gas-discharge means into which the electrical conducltbrs extend to control the 'gas dischargefmeans insaccordance withreradio mares; received from theifiobjectlby thel'radiot-wa've:receivinglmeans;

l 2120;;An:electriczsystem:having,:in:lc0mbination, radio-wave receiving :means' for- ;receivinge radio waves:fromzan.obfi ectccomprising' antennaaimeans lproy ldedwwit electrical. conductorsyie gas-dis:- charge means, and" means f0I StI ikingn3fibaCkr groundlgas'gdischargein'thegas-discharge means, therelectrical: conductorsrextending into the gasdischarge; means to modify; the: backgroun'dggas discharge in accordancewwith athemradio waves received from the object by "the ;radi,o-.wave -'receivingwmeansr w 7 .21; "An" electric? systems having; inf combina: tion, dipole: antennawmeans for receiving-:-radio .waves'w-from an: obj ect provided with :integral electrical conductorsand gasedischargel means into which the electrical conductors extendeto control the gas-dischargemeans in accordance with-the radio-Wave, 7 energy sreceived from rthe object by the radio-wave-receiving means; 22. An electricsystem-having in combination, radio-wave receiving means for ereceiving radio waves from an object comprisingthermoelectriccouple (means provided with electrical conductors and. gas-discharge l means into which; the, elec trical. conductors extend vto controlthe gas-dis;- charge means in accordancewith: radio [waves received. from the object by the-radio-wave receiving means. I H 23. electric system. having, in combination, radio-wave receiving/means for receiving radio waves. from .an object comprising..,thermoelectriccouple means provided [with 4 electrical conductors, .l ga's'disch'arge ,means,.f and. means for-listrikim; a background g'a's discharge winlthe" ga's' -dis charge means," the electrical conductors lex'tending, ir'itolthe.gas-discharge. means to .modify'ithe backgroundgas dischargein accordance with the radio waves received fromf the obj ectiby. the. radio=wavereceiving means.

524, An electric system'having, in-icombina'tion, a plurality of "thermoelectric couplejradio-wave receiving: elements for Ireceiving radio waves,

means for focusing radio waves from'a'n object 7 upon the radio-wave receiving elementsilll'l'mi heating means" electrically connecte'dito each lelee ment, means 'for. illuminating ,tl'i'eilluminating means7and. means controlled in accordancefiith the radiofiwaves received. by theiradio=wavef rec'eivingelern'ents' for controlling theintenslt pr illuminationnf theifluminating "mjeans'to p oducea'likenessof the object. r

' ROBERT HARVEYBINES.

REFsRENcEs cITE .fIlle following references are .of.I..record in,. the file of. this patent :UNITED' s'rA'rEsrsATEN'rs Number Name Date 1 ,'7 1l,481- 3 Schmierer ""Dec. 31,1929 1,789,52l *Feing01d *J an"'20j1931 "2,015,885 Dallenbach' Oct. ;'--'1935 2,083,292 'Cawley 'Q June' 8:,"1937 ,123,242 Hollman July 12;19-38 2,153,181 Gerhard i -Aprn4; 1939 4 2,155,471 A 2,306,272

, f1 FOREIGNQPATENTS J l :Number Country iii-Data 520,778 I 

